Mini-face putter with grooves

ABSTRACT

A golf putter head having a vertically rounded face and one or more grooves or projections. In some embodiments the putter head ( 10, 110, 210, 310, 410, 510, 610 ) has an elongate flat blade (16, 116, 216, 616) for contacting a golf ball ( 30 ). The elongate flat blade ( 16, 116 ) is of narrow thickness and has grooves or projections in the front edge. Further provided are golf putter heads ( 310 ) having a rounded front edge ( 313 ) with grooves or projections. The grooves of either type of putter can optionally have linear inserts within the grooves to provide the projections or the projections can be an integral part of the front edge of the putter heads ( 16, 116, 310 ). The golf putter heads ( 10, 110, 310 ) can have weights which can be secured in slots on the bottom of the putter heads to allow for various weighting configurations. The putter heads ( 10, 110, 310 ) have contact areas ( 34 A,  34 B) between the front edge ( 16, 116, 310 ) when it strikes a golf ball ( 30 ) which is linear, of narrow width and horizontal in orientation.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent application Ser. No. 10/672,185, filed Sep. 26, 2003.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

BACKGROUND OF THE INVENTION

(1) Field of the Invention

The present invention relates generally to golf equipment, and more particularly to golf putter heads. Specifically, the present invention relates to a putter head having a grooved striking face.

(2) Description of the Related Art

The traditional putter has a vertical blade with a flat surface and a vertical height usually one inch (25 mm) or greater. Subsequent traditional putters have a similar geometry on the face allowing for flat, convex, but not concave faces. The contact surface is often distinguished by the shape of the mass behind the vertical face. There have been putters with curved contact faces from heel to toe on the putter. This feature is permissible under United States Golf Association (U.S.G.A.) rules. There also have been putters that are totally cylindrical in geometry. Existing putters come in many sizes and geometries. There is often heel to toe weighting to resist the turning of the vertical positioned putter blade.

The rules of golf equipment are controlled by the U.S.G.A. for America. The Royal and Ancient Golf Club of St. Andrews (R.&A.) is the governing authority for the rules of golf in more than one hundred affiliated nations. More recently, in a written ‘statement of principles’ published jointly by the R.&A. and the U.S.G.A., it was acknowledged that, “History has proved that it is impossible to foresee the developments in golf equipment which advancing technology will deliver.” However, both the R.&A. and the U.S.G.A. remain vigilant when considering the equipment rules. The main objective of U.S.G.A. Rules 4 and 5 and Appendices II and III is to protect golf's best traditions, to prevent an over-reliance on technological advances rather than skill, and to ensure that skill is the dominant element of success throughout the game. Therefore, any club design must consider these rules if the club is to be deemed legal by the governing authorities of golf. Any putter must be compatible with the U.S.G.A. rules of golf in regards to being plain in shape, with runners that do not extend into the face, a width that is greater than the depth, a face without concavity, a face angle of no more than fifteen degrees, and an angle of shaft to the head of ten degrees incline or greater. There is no rule regarding the vertical depth of the face of the putter. When there are grooves in the putter face, and if a groove exceeds 0.035 inches in width and 0.020 inches in depth, the following guidelines apply: 1. The width may not exceed 0.06 inches. 2. The width to spacing ratio must be no less than 1:1. 3. The depth must be less than the width, and may not exceed 0.04 inches. As for the grooves on irons and woods, the grooves on a putter must not have sharp edges.

U.S. Pat. No. 4,165,076 to Cella teaches a putter with the blade face formed with a longitudinal edge, which is the normal ball striking component of the golf club, being located above the center line of the ball in blade striking position. On the reverse side of the blade there is provided a secondary ball striking edge located below the center line of the ball.

U.S. Pat. No. 5,467,987 to Perkins et al. teaches a golf putter having a club head with a striking face comprising a striking edge defined by at least two substantially planar surfaces which engages a golf ball at a point below the center of the golf ball.

U.S. Pat. No. 6,464,598 to Miller teaches a golf club with a wedge face, a rounded sole, and a putting face located along a blade area between the wedge face and a front portion of the rounded sole. The putting face is located at a height above the crown of the rounded sole so that the putting face strikes a golf ball above the equator of the ball to impart top spin when putting.

U.S. Design Pat. No. D396257 to Spano teaches an ornamental design for a golf club head. It is not clear from the drawings how the club is used.

Japanese Patent Publication No. 8-150233 to Hotta et al. discloses a golf putter having a thin-plate head portion. The thin-plate head portion can have protrusion constructed of a very light-weight material on the bottom surface or top and bottom surfaces of the thin-plate head portion, but does not provide grooves or provide for variable weighting of the putter.

U.S. Pat. No. 4,529,202 to Jacobsen discloses a golf club head suitable for use on putting surfaces having a generally planar blade member with disc-like members which provide a predetermined weight to the toe and heel ends golf club head.

U.S. Pat. No. 6,849,004 to Lindsay discloses a golf-putter head having a grooved flat impact face with a multiplicity of substantially parallel ridges extending lengthwise along the head. Lindsay does not disclose a golf putter head having a rolled face vertically with a radius less than that of a golf ball.

U.S. Pat. No. 5,193,806 to Burkly discloses a spin control chipper-putter with grooves. The round golf club head has grooves which extend along upper and lower portions of the putter head. The grooves are omitted to provide a smooth surface on the right and left faces of the putter head.

U.S. Pat. No. 5,637,044 to Swash discloses the use of concentric grooves on the face of a putter to increase accuracy. The putter has a conventional flat putting face.

While the related art describes alternative ways to address improving putter performance, there is still a need for a superior solution.

OBJECTS

Therefore, it is an object of the present invention to provide a putter head having a grooved striking face. It is still further an object of the present invention to provide a putter with a geometry such that the contact area between the putter and the ball at impact is linear and essentially horizontal. These and other objects will become increasingly apparent by reference to the following description and the drawings.

SUMMARY OF THE INVENTION

The present invention provides a golf putter head with a curved front edge used for striking a golf ball in an essentially linear contact area horizontal to the ground when putting and an opposed back edge, a length defined between a toe edge which extends from the curved front edge to the back edge of the blade and an opposed heel edge, and a thickness defined between a top side bordered by the edges and an opposed bottom side, the improvement which comprises one or more grooves on the curved front edge at least adjacent to a ball contact portion of the head defined by two or more ridges between the grooves, wherein the front edge is curved vertically such that the front edge strikes the golf ball on a small contact area upon no more than two of the ridges.

In some embodiments the front edge is curved vertically with a radius of curvature less than a radius of the golf ball. In further embodiments the front edge has three grooves. In still further embodiments the one or more grooves are parallel and extend along the length of the front edge from toe edge to heel edge, so as to be horizontal to the ground when putting. Preferably, the front edge used for striking a golf ball is provided as an interchangeable face. In further embodiments the one or more grooves have a width of no more than 0.06 inches, a depth of no more than 0.04 inches, and a width to spacing ratio of at least 1:1. In still further embodiments the one or more grooves have a width of 0.06 inches, a depth of 0.04 inches and are separated by 0.07 inches. In some embodiments of the putter head, the putter face has a radius of 0.5 to 0.75 inches. In still further embodiments the grooves have a 0.06 inch width with a 0.06 inch space between the grooves, a depth which does not exceed 0.04 inches, and wherein the ridges are without sharp edges. In still further embodiments the thickness of the front edge of the putter head is less than about 0.25 inch (6.4 mm). In further embodiments the thickness of the putter head varies from the front edge to the back edge.

The present invention provides a golf putter head with a front edge used for striking a golf ball in an essentially linear contact area horizontal to the ground when putting and an opposed back edge, a length defined between a toe edge extending from the front edge to the back edge of the blade and an opposed heel edge, and a thickness defined between a top side bordered by the edges and an opposed bottom side, the improvement which comprises one or more projections on the curved front edge at least adjacent to a ball contact portion of the head, wherein the front edge is curved vertically such that the front edge usually strikes the golf ball on a small contact area upon no more than two of the projections with typical putting force.

In some embodiments the front edge is curved vertically with a radius of curvature less than a radius of the golf ball. In further embodiments the front edge has three projections. In further embodiments the one or more projections are parallel and extend along the length of the front edge from toe edge to heel edge, so as to be horizontal to the ground when putting. Preferably, the front edge used for striking a golf ball is provided as an interchangeable face. In still further embodiments the one or more projections have a width of 0.06 inches and are separated by 0.07 inches. In still further embodiments the putter face has a radius of 0.5 to 0.75 inches. In still further embodiments the projections have a 0.06 inch width and have a 0.06 inch space between the ridges. In still further embodiments the thickness of the front edge of the putter head is less than about 0.25 inch (6.4 mm). In still further embodiments the thickness of the putter head varies from the front edge to the back edge. In still further embodiments the projections are parallel to one another and are horizontally oriented. In still further embodiments the projections are disposed perpendicularly to a tangent of the face of the putter head.

The present invention provides a golf putter having a shaft with a grip at a proximal end and a head at a distal end of the shaft for contacting a golf ball on the ground during putting of the golf ball, the improvement in the head which comprises: an elongate flat blade having opposed ends, with a top side and a bottom side, and a first linear edge extending therebetween, wherein the top side of the blade is mounted on the distal end of the shaft and the first linear edge acts as a striking face for the golf ball and strikes the golf ball in an essentially linear contact area horizontal to the ground, wherein the striking face is curved vertically with one or more grooves at least adjacent to a ball contact portion of the striking face. The grooves can extend along the length of the striking face, however they can extend less than the entire length of the first linear edge.

The present invention provides a golf putter having a shaft with a grip at a proximal end and a head at a distal end of the shaft for contacting a golf ball on the ground during putting of the golf ball, the improvement in the head which comprises: an elongate flat blade having opposed ends, with a top side and a bottom side, and a first linear edge extending therebetween, wherein the top side of the blade is mounted on the distal end of the shaft and the first linear edge acts as a striking face for the golf ball and strikes the golf ball in an essentially linear contact area horizontal to the ground, wherein the striking face is curved vertically with one or more grooves at least adjacent to a ball contact portion of the striking face; and a runner provided on the bottom side of the blade wherein during putting, the runner acts to space the bottom side of the blade from the ground.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a top view of a putter head (10) of the present invention having toe and heel projections (22, 23) bordered by a curvilinear ledges (22A, 23A).

FIG. 1A illustrates a cross-sectional view of alternative embodiment of the putter head of FIG. 1 with two curved striking faces. One curved striking face having grooves (14) is at the front edge (16A) and a second striking face having grooves (14′) is at the back edge (16B′) of the putter head (10′).

FIG. 2 illustrates a front view of the putter head (10) showing a front edge (16A) having grooves (14).

FIG. 3 illustrates a bottom view of the putter head (10) having both small weights (17A) and both large weights (17B) secured in the slots (24, 25).

FIG. 4 illustrates a bottom view of the putter head (10) having large weights (17B) secured towards the back edge (16B) in the slots (24, 25).

FIG. 5 illustrates a bottom view of the putter head (10) having small weights (17A) secured towards the back edge (16B) in the slots (24, 25).

FIG. 6 illustrates a bottom view of the putter head (10) without any weights (17A, 17B) attached in the slots (24, 25) showing holes (21) for attachment.

FIG. 7 illustrates a cross-sectional view of the putter head (10) with a single curved striking face taken along line 7-7 of FIG. 3 showing small weights (17A) and large weights (17B) attached with screws (19) in holes (21) in the heel slot (25).

FIG. 8 illustrates a top view of another putter head (110) of the present invention having a rectangular toe projection (122) and a rectangular heel projection (123).

FIG. 9 illustrates a front view of the putter head (110) showing a front edge (116A) having grooves (114).

FIG. 10 illustrates a front view of an elongate flat blade golf putter head 210 according to the present invention having a single groove 219.

FIG. 11 illustrates a heel view of the golf putter head 210 of FIG. 10.

FIG. 12 illustrates a cross-section view of the golf putter head 210 of FIG. 10 taken along the line 12-12 of FIG. 10.

FIG. 13 illustrates a face view of another putter head (310) according to the present invention with linear grooves (320) on the front edge (315).

FIG. 13A illustrates a face view of an alternative configuration of the putter head of FIG. 13 having circular grooves (320′) configured as a target on the front edge (315) of the putter head (310′).

FIG. 14 illustrates a heel end view of the golf putter head (310).

FIG. 15 illustrates a top view of the golf putter head (310).

FIG. 16 illustrates a back view of the golf putter head (310).

FIG. 17 illustrates a bottom view of the golf putter head (310).

FIG. 18 illustrates a golf ball (30) showing a typical contact area (34A) resulting from contact with a grooved thin-blade putter head (110) of the present invention.

FIG. 18A illustrates a closer view of the designated region in FIG. 18.

FIG. 19 illustrates a front view of a putter head (110) of FIG. 8 and FIG. 9 showing the typical contact area (34A) resulting from contact with the golf ball (30) of FIG. 18.

FIG. 19A illustrates a closer view of the designated region in FIG. 19.

FIG. 20 illustrates a golf ball (30) showing a typical contact area (34B) resulting from contact with a grooved round face putter head (310) of the present invention.

FIG. 20A illustrates a closer view of the designated region in FIG. 20.

FIG. 21 illustrates a front view of a golf putter (310) illustrated in FIG. 13 through FIG. 17 showing the contact area (36B) resulting from contact with the golf ball (30) of FIG. 20.

FIG. 21A illustrates a closer view of the designated region in FIG. 21.

FIG. 22 illustrates a face view of the putter head (310) having four projections (330) along the front edge (315).

FIG. 23 illustrates a cross-sectional view of the putter head (310) taken along line 20-20 of FIG. 22 showing the four rounded projections (330) along the front edge (315).

FIG. 23A illustrates a cross-sectional view of a putter head (310′) taken along line 20-20 of FIG. 22 showing four horizontally oriented projections (330′) having sharp ledges along the front edge (315).

FIG. 23B illustrates a cross-sectional view of a putter head (310″) taken along line 20-20 of FIG. 22 showing four projections (330″) having sharp ledges which project perpendicularly to a tangent of the curve of the front edge (315).

FIG. 24 illustrates a right-handed face view of a cylindrical putter head (410) having grooves (430A) in the right-handed face (439) and grooves (430B) the left-handed face (438).

FIG. 25 illustrates a heel view of the cylindrical putter head (410) having grooves (430A) in the right-handed face (439) and grooves (430B) the left-handed face (438).

FIG. 26 illustrates a top view of the cylindrical putter head (410) having grooves (430A) in the right-handed face (439) and grooves (430B) the left-handed face (438).

FIG. 27 illustrates a face view of another embodiment of a cylindrical putter head (510) having grooves (430A) in the front (439).

FIG. 28 illustrates a top view of the cylindrical putter head (510) having grooves (430A) in the front (439).

FIG. 29 illustrates a heel view of the cylindrical putter head (510) having grooves (430A) in the front (439).

FIG. 30 illustrates a front view of another putter head (610) of the present invention showing a front edge (616A) having a single groove (614).

FIG. 31 illustrates a top view of the putter head (610) of FIG. 30.

FIG. 32 illustrates a back view of the putter head (610) of FIG. 30.

FIG. 33 illustrates a heel view of the putter head (610) of FIG. 30.

FIG. 34 illustrates a bottom view of the putter head (610) of FIG. 30.

FIG. 35 illustrates a cross-sectional view of the putter head (610) taken along line 35-35 of FIG. 30.

FIG. 36 illustrates a cross-sectional view of the putter head (610) taken along line 36-36 of FIG. 30.

DETAILED DESCRIPTION OF THE INVENTION

All patents, patent applications, government publications, government regulations, and literature references cited in this specification are hereby incorporated herein by reference in their entirety. In case of conflict, the present description, including definitions, will control. Definitions for the following terms are provided to promote a further understanding of the present invention.

The term “contact area” as used herein refers to the area on either a putter blade or a golf ball where there is contact between the ball and the putter blade.

The term “proximal” as used herein refers to the direction or portion of a putter near to the golfer when in use.

The term “distal” as used herein refers to the direction or portion of a putter away from the golfer when in use.

The term “front” as used herein refers to the edge of the putter head used by a right handed golfer as a striking surface for contacting a golf ball during putting. A “face” as used herein refers to any surface used to strike a golf ball. Some putters having a central shaft can be used in a right or left handed fashion under U.S.G.A. rules. Right handed designations are used herein with reference to the Figures, however left handed uses and configurations are encompassed by the present invention. In some embodiments there can be the same hitting surface on both front and back. The two opposing front and back striking surfaces each have grooves so as to conform with regulations. In this case the front and the back are each a striking face, since either one can be used to strike the golf ball.

The term “ball contact portion” as used herein refers to a part of the striking face which is at or near to the center of the face. It is intended to be used for striking the golf ball. It can be located on the front and/or the back of the putter head when it can be used to strike the golf ball.

The term “back” as used herein refers to the side of the putter head opposed to the front striking face. In some embodiments of the putter heads of the present invention the back is also configured as a striking face with grooves so as to conform to USGA and R&A rules.

The term “toe” as used herein refers to the side of the putter head which is distal to the golfer when putting.

The term “heel” as used herein refers to the side of the putter head which is proximal to the golfer when putting.

The term “horizontal” as used herein refers to an orientation parallel the ground upon which the golf ball lies. When used in reference to the putter head, it refers to a line which is horizontal when the putter addresses the golf ball. Therefore the term “horizontal” refers to the ground and/or the bottom side of the club.

The term “vertical” as used herein refers to an imaginary line which is normal to the horizontal plane of the ground upon which the golf ball lies.

The term “fastening means” as used herein refers to any means known in the art, conforming to the rules of golf, of fastening, including screws of a number of types, bolts, pins, and clips. One preferred fastening means is an Allen screw.

The term “weights” as used herein refers to any of a variety of solid materials, preferably metal, having a size and shape capable of being removably secured by a fastening means within a slot in the putter head, which can have a wide range of densities and masses. Preferably the weights are constructed of a variety of metals having different densities, however the weights can be constructed of lighter materials.

The term “target” refers to a set of two or more concentric circular grooves.

A putter head with a rounded vertical face which has the advantage of producing a straight smooth roll of the ball, even when the toe is inadvertently up or down. It has been demonstrated on a robot in a laboratory that if the typical flat faced putter (with a 4 degree incline) is elevated even 3.6 degrees that the resultant ball roll will be 6 inches off line towards the player's stance on a 10 foot putt. This is not so with a putter with a convex vertical face. The ball impact area on the putter face is lower on the face and towards the heel of the club, but the resultant geometry of the impact is the same as if the putter were horizontal and square to the ball. The resultant roll is straight. Robotic testing confirmed the efficiency of each of the disclosed embodiments herein.

According to the rules of golf, a putter with two opposing striking surfaces will require grooves on both the front edge and back edge. Therefore, to be in conformity with the rules, any putter herein can have grooves on both the front edge and the back edge so as to provide the same hitting surface on front and back. Additionally, the grooves of the present invention can be in a variety of configurations, including grooves in a pixel, crosshatched, or a circular format which appears as a target on the striking face. The grooves can extend the entire length of a face of the putter head, or only be placed at or adjacent to the ball contact portion of the striking face.

The present invention provides a putter with a vertically convex surface and grooves. The convex face can be of any radius, but preferred embodiments of the putter head have a rounded face with a vertical curvature having a radius which is less than that of a golf ball. There can be any number of grooves, including only one. The grooves can be of any size, width and depth, but preferred embodiments are grooves which conform to USGA and the Royal & Ancient (R&A) rules of Golf.

The grooves can be like those which can be used on the other clubs according to the specifications set out in USGA Guide to the Rules on Clubs and Balls, Supplement A: “How to Determine Whether Grooves Conform”. According to Appendix II, 5c (i) of the Rules of Golf markings in the impact area must not have sharp edges or raised lips as determined by a finger test. Grooves in the impact area must meet the following specifications, according to the Rules: (1) A series of straight grooves with diverging sides and a symmetrical cross-section may be used. (2) The width and cross-section must be consistent across the face of the club and along the length of the grooves. (3) Any rounding of groove edges shall be in the form of a radius which does not exceed 0.020 inches (0.508 mm). (4) The width of the grooves must not exceed 0.035 inches (0.9 mm), using the 30 degree method of measurement on file with the United States Golf Association. (4) The distance between edges of adjacent grooves must not be less than three times the width of a groove, and not less than 0.075 inches (1.905 mm). (5) The depth of a groove must not exceed 0.020 inches (0.508 mm).

In a first embodiment of the putter head of the present invention the front edge has one or more grooves in the face. The golf putter can be a round or rolled face putter. The problem which this putter solves is that on a round or rolled face with a smooth polished surface, a ball hit above or below the equator has the potential to slide a microscopic distance on the face which then elevates (up side) or depresses (down side) the ball trajectory. If the putter face has a groove this undesirable result would be minimized or eliminated. In addition the already horizontal impact geometry between the club and the ball would be more linear and of less surface area. There are multiple benefits to the grooves.

The purpose of the grooves are to further minimize the surface of the impact geometry, and maximize the linear nature of the impact geometry. Further purposes of the grooves is that they provide for traction on the ball at club-ball impact, especially when the impact on the round club face is above or below the equator. The absence of the grooves on a convex vertical striking area has the potential to have the ball slide up or down the face. The grooves act to avoid this undesirable result and give enhanced control to the resultant direction of the putt. As illustrated in the Figures, the grooves increases the linear nature of the contact area of the putter head face with the golf ball. The grooves lessen the total contact area made with a golf ball than a face lacking grooves. The grooves conform to USGA and Royal & Ancient rules, but can be used on nonconforming clubs for a novelty club.

The contact geometry surface area is related to the force of the impact. It is greater with a greater impact and less with a lesser impact. It can be as little as a portion of exposed surface to multiple grooves and linear surfaces. The grooves can extend over any length of the face from a short length to the entire length of the face. There can be any combination of length and width of the grooves on the face. The grooves can be on an insert constructed of any material on the face and have any of the configurations disclosed herein. The putter can have one or two striking surfaces. In the latter case the surfaces will have the same geometry.

The putter head can be constructed having interchangeable faces of varying materials and geometry, including but not limited to those which conform to the rules of golf. The putter heads of the present invention preferably have variable weighting. The weight can be placed in any of a variety of ways, not necessarily symmetrical, so as to adjust for and accommodate the individual golfer's stroke.

The grooves or projections of any of the putter head of the present invention can all be parallel to one another and be horizontally oriented. Alternatively they can all be disposed perpendicularly to the tangent of the arc of the face of the putter head, ie. aligned normal to the arc of the face. They can also be a combination of either of these configurations, with some grooves horizontally oriented and others perpendicularly oriented. The angle of cut of the grooves can be of any orientation, i.e. crosshatch and circular orientations.

The grooves do not necessarily, but will preferably conform to USGA and R&A rules. The grooves can be as those on a regular club as outlined in the rules of golf. In some embodiments the grooves have a width of 0.06 inches, a depth of 0.04 inches and are separated by 0.07 inches. The design of the groove will be USGA conforming. The groove could be spaced farther. In preferred embodiments, the grooves are at or nearly the 0.07 inch minimum spacing allowed by USGA rules. In some embodiments, the grooves are perpendicular to the tangent of the arc of the face. In further embodiments the grooves are parallel to one another and not tangential to the curve of the face. In further still embodiments the grooves are along the horizontal axis of the putter face.

In another embodiment of the putter head of the present invention, the putter head has one or more ridges on the front edge. In some embodiments, the ridges are provided by a projecting ridge along the front edge. In further embodiments the ridges and the face of the putter are constructed from a single piece of material such as titanium. Preferably the face is constructed of titanium to be more resistant to abrasion and denting in any of the embodiments. The material is constructed with a continuous or varying weight distribution and for abrasion resistance. Additionally, different materials can be provided for a different “feel” and sound at impact to provide important biofeedback and psychomotor performance.

In one embodiment the putter head has a rolled face vertically with a radius less than that of a golf ball. In preferred embodiments the putter face has a radius of 0.5 to 0.75 inch with several grooves of 0.06 inch width and 0.06 inch space between the grooves. The depth of the grooves does not exceed 0.04 inches and the grooves do not have sharp edges. The putter face can comprise one or more grooves which are placed at any angle relative to one another. Preferably the grooves are perpendicular to the tangent of the curve of the face. In some embodiments the grooves can be horizontal to another and not tangential to the curve of the face. The putter head configuration with grooves decreases the surface area of the club face to ball contact. It also assures the likelihood of a horizontal geometry of the impact strike pattern.

A round face putter makes a linear impact geometry on the face and ball. The surface area is less than that made by contact with a flat putter face and a round ball. The surface area of impact can be made smaller by placing grooves in the round face. Grooves have been in flat face putters. The geometry of the impact becomes more linear with grooves on a round face, as illustrated in the Figures. Grooves are permitted on putter faces according to USGA rules, and can be different than on regular club faces.

In one embodiment, the golf putter head of the present invention comprises an elongate flat blade which has a width defined between a front edge used for striking a golf ball and an opposed back edge. The length of the blade is defined between a toe edge, which extends from the front edge to the back edge of the blade and an opposed heel edge. The thickness of the blade is defined between a top side, bordered by each of the edges, and an opposed bottom side nearest to the ground when putting. The top side of the blade has an opening, into which a shaft can be affixed. The shaft can be affixed to the putter head by welding or any means known in the art. Optionally the shaft is affixed using a hosel. The bottom side of the blade has two or more slots, adapted to receive weights, which extend along the width of the blade. Two or more weights can be secured into one of the slots by one or more fastening means attached in holes in the slots in the bottom side of the blade. The weights provide the putter head various weighting configurations. Preferred weighting configurations place the center of mass of the putter head towards the back of the putter head (posterior) and towards the bottom side of the blade (inferior). Preferably, the putter has heel/toe weighting. The total weight of the putter head can be adjusted by adding or removing the weights. The optimal weighting can be determined by robotic testing or by trial and error in the golfer's hands.

The putter head can also be any of the putter head embodiments described herein and having an interchangeable face. The interchangeable faces can be screwed on or attached by any means known in the art. The interchangeable faces can be of a variety of configurations. The face can be with an elevation from vertical of zero to four degrees; a rolled (rounded) face having a radius which is less than that of a golf ball; a rolled (rounded) face of any radius with grooves; a rolled (rounded) face with linear grooves to provide ridges constructed of any of a number of materials; a rolled (rounded) face having linear elevated projections. The face is preferably constructed of titanium so as to be more resistant to abrasion and denting. The grooving can be on a putter to minimize the contact geometry, especially the larger grooving permitted on putters under the rules of golf.

A first embodiment of the putter head 10 of the present invention is illustrated in FIG. 1 to FIG. 7 described in commonly owned U.S. patent application Ser. No. 11/050,062 to Johnson hereby incorporated herein by reference in its entirety. In this embodiment, the putter head 10 includes an elongate flat blade 16 with a runner 18. The elongate flat blade 16 includes a front edge 16A and an opposed back edge 16B. A convexly rounded toe edge 16C extends from the front edge 16A to the back edge 16B of the blade. On an opposite side of the blade a convexly rounded heel edge 16D extends from the front edge 16A to the back edge 16B of the blade. A thickness of the blade 16 is defined between a top side 16E, bordered by each of the edges, and an opposed bottom side 16F. The curved front edge 16A of the blade 16 used as a striking face for contacting a golf ball between the ends defined by toe edge 16C and heel edge 16D, and the parallel top side 16E and bottom side 16F. The front edge 16A of the blade 16 has three parallel grooves 14, running the length of the striking face from toe edge 16C to heel edge 16D. One of the grooves is located centrally along the height of the striking face, while the other two are located towards the top side 16E and the bottom side 16F of the front edge 16A.

Appendix II, 4c of USGA Rules states: “The clubhead shall only have one striking face, except that a putter may have two such faces if their characteristics are the same, and they are opposite each other.” According to the USGA Guide to the Rules on Clubs and Balls “Determining whether a surface constitutes a second (or third) striking face is often a matter of opinion. However, in general, a surface should be considered an additional striking face if: the area is flat and it is clearly designed to be used for striking the ball, or it is opposite the intended face and consists of a flat surface of a different loft and/or material, or it is a flat surface on the toe and/or heel of a cylindrical, rectangular or square head design which could effectively be used to strike the ball, or it could otherwise effectively be used to strike the ball.” To provide putters which conform to the Rules, each of the putter heads of the present invention can be provided having a curved striking face with grooves on a back side of the putter opposed to the front striking face. For example, FIG. 1A illustrates a cross-sectional view of an alternative embodiment of the putter head of FIG. 1 which has two opposed striking faces. One curved striking face having grooves 14 is on the front edge 16A and a second curved striking face having grooves 14′ is on the back edge 16B′ of the putter head 10′. The rest of the putter head 10′ of FIG. 1A is identical to putter head 10 of FIG. 1.

The blades 16 of these putter heads 10, 10′ are not flat on the top side 16E, but rather have a toe projection 22 and a heel projection 23 which are disposed towards the periphery of the putter heads adjacent to the toe edge 16C and heel edge 16D, respectively. On the top side 16E of the blade 16, the toe projection 22 protrudes from the top side 16E of the putter head 10 at curvilinear toe ledge 22A. The toe projection 22 extends along the length of the blade 16 from the convexly rounded toe end 16C to a curvilinear toe ledge 22A. The curvilinear toe ledge 22A curves back from the intersection of front edge 16A and toe edge 16C to back edge 16B, extending the width of the putter head. At the rounded heel end 16D of the top side 16E is a heel projection 23 which protrudes from the top side 16E of the putter head 10 at a curvilinear heel ledge 23A. The heel ledge 23A curves back from the intersection of front edge 16A and heel edge 16C to back edge 16B, extending the width of the blade 16. The toe projection 22 and heel projection 23 provide the putter head 10 peripheral toe-heel weighting for stability and posterior weighting.

An indented sighting line 20 extends along the width of the blade 16 centrally with respect to the length of the blade 16 from front edge 16A to the back edge 16B. The sighting line 20 is useful for alignment of the putter head 10 when addressing the golf ball. Optionally, a runner 18 is attached to the bottom side 16F of the blade 16. The runner has an convex outer surface 18C projecting from the bottom side 16F of the blade 16 from a front end 18A near the front edge 16A of the blade 16 to a back end 18B near the back edge 16B of the blade 16. The outer surface 18C of runner 18 keeps the blade 16 the proper distance from the putting surface, and allows for a smooth swinging movement during the stroke, by minimizing drag due to small surface area contact with the ground.

FIG. 3 to FIG. 5 illustrate bottom views of the putter head (10) with small weights (17A) and large weights (17B) attached to provide different weighting configurations. FIG. 3 and FIG. 7 illustrate a heavily weighted putter head configuration of the putter head 10 wherein small weights 17A are secured by Allen screws 19 towards the front edge 16A of the blade 16 in both the toe slot 24 and the heel slot 25. In addition large weights 17B are secured by Allen screws 19 towards the back edge 16B of the blade 16 in both the toe slot 24 and the heel slot 25. This configuration results in maximal weighting of the putter head 10. FIG. 4 illustrates a moderately weighted putter head configuration having only large weights 17B secured by Allen screws 19 in the holes 21 and situated towards the back edge 16B of the blade 16 in both the toe slot 24 and heel slot 25. This configuration results in posterior, inferior weighting of the putter head 10 and moderate weighting. FIG. 5 illustrates a lightly weighted putter head configuration having only small weights 17A secured by Allen screws 19 in the holes 21 and situated towards the back edge 16B of the blade 16 in both the toe slot 24 and heel slot 25. This configuration results in posterior, inferior weighting of the putter head 10 and light weighting. FIG. 6 illustrates a bottom view of the putter head 10 without either the small weights 17A or the large weights 17B in either the toe slot 24 or the heel slot 25. This result in the lightest putter head 10 configuration. Additionally, any combination of the weights can be inserted into either or both of the slots so that the putter head is not symmetrically weighted.

A second embodiment of the putter head 110 of the present invention is illustrated in FIG. 8 and FIG. 9 also described in commonly owned U.S. patent application Ser. No. 11/050,062 to Johnson hereby incorporated herein by reference in its entirety. In this embodiment, the putter head 110 includes an elongate flat blade 116 with a runner 118. The elongate flat blade 116 includes a front edge 116A and an opposed back edge 116B. A convexly rounded toe edge 116C extends from the front edge 116A to the back edge 116B of the blade. On an opposite side of the blade a convexly rounded heel edge 116D extends from the front edge 116A to the back edge 116B of the blade. A thickness is defined between a top side 116E, bordered by each of the edges, and an opposed bottom side 116F. The front edge 116A of the blade 116 used as a striking face for contacting a golf ball between the ends defined by toe edge 116C and heel edge 116D, and the parallel top side 116E and bottom side 116F. The front edge 116A of the blade 116 has three parallel grooves 114, running the length of the striking face from toe edge 116C to heel edge 116D. One of the grooves is located centrally along the height of the striking face, while the other two are located towards the top side 116E and the bottom side 116F of the front edge 116A.

The blade 116 is not flat, but rather has a toe projection 122 and a heel projection 123 towards the periphery of the putter head adjacent to the toe edge 116C and heel edge 116D, respectively. The toe projection 122 protrudes from the top side 116E of the putter head 110. Near the rounded toe end 116C of the top side 116E is a rectangular toe projection 122 raised from the top side 116E of the putter head 110 at a toe ledge 122A and extending the width of the putter head 110. At the rounded heel end 116D of the top side 116E is a rectangular heel projection 123 raised from the top side 116E of the putter head 110 at a heel ledge 123A and extending the width of the putter head 110. An indented sighting line 120 extends along the width of the blade 116 centrally with respect to the length of the blade 116 from front edge 116A to the back edge 116B. The toe projection 122 and heel projection 123 provide the putter head 110 peripheral toe-heel weighting for stability.

The sighting line 120 is useful for alignment of the putter head 110 when addressing the golf ball. Optionally, a runner 118 is attached to the bottom side 116F of the blade 116. The runner has an convex outer surface 118C projecting from the bottom side 116F of the blade 116 from a front end 118A near the front edge 116A of the blade 116 to a back end 118B near the back edge 116B of the blade 116. The outer surface 118B of runner 118 keeps the blade 116 the proper distance from the putting surface, and allows for a smooth swinging movement during the stroke. On the bottom side 116F of the blade 116 is a toe slot 124 near toe edge 116C and a heel slot 125 near heel edge 116D, each extending the width of the putter head 110 and adapted to receive small weight (not shown) and large weights 117B. This allows for various weighting configurations identical to those shown for the first embodiment of the putter head 10 as illustrated in FIG. 3 through FIG. 6 described previously.

FIG. 10 through FIG. 12 illustrate a further embodiment of a putter head 210 of the present invention comprising a single groove 219 in the front edge 216A of blade 216, described in commonly owned U.S. patent application Ser. No. 10/672,185 to Johnson hereby incorporated herein by reference in its entirety. The putter head 210 comprises an elongate flat blade 216 with a runner 218. The elongate flat blade 216 includes a front edge 216A and an opposed back edge 216B. A toe edge 216C extends from the front edge 216A to the back edge 216B of the blade. On an opposite side of the blade a heel edge 216D extends from the front edge 216A to the back edge 216B of the blade 216. A thickness of the blade 216 is defined between a top side 216E, bordered by each of the edges, and an opposed bottom side 216F. The front edge 216A of the blade 216 used as a striking face for contacting a golf ball between the ends defined by toe edge 216C and heel edge 216D, and the parallel top side 216E and bottom side 216F. The front edge 216A of the blade 216 has a single groove 219, running the length of the striking face from toe edge 216C to heel edge 216D. FIG. 10 shows the putter head 210 from a front view, showing the groove 219 in the front edge 216A of blade 216. Groove 219 runs horizontally across the center line of front edge 216A of the blade 216. In one embodiment, groove 219 is approximately 0.06 inches (1.5 mm) wide and approximately 0.04 inches (1.0 mm) deep and extends from heel edge 216D to toe edge 216C. FIG. 11 illustrates a heel view and FIG. 12 illustrates a cross-section along the line 12-12 of FIG. 10 both showing the groove 219 having these dimensions.

The present invention further provides the putter head 310 illustrated in FIG. 13 through FIG. 17 described in commonly owned U.S. patent application Ser. No. 10/915,610 to Johnson hereby incorporated herein by reference in its entirety. The putter head 310 is an elongate blade having a first linear edge which is a front edge 315 of the putter head 310 used as a face for striking a golf ball. The front edge 315 of the putter head 310 has a vertical radius which is less than that of the golf ball. The front edge 315 has three parallel grooves 320 running the length of the striking face from toe edge 313 to heel edge 314. One of the grooves is located approximately central along the height of the striking face, while the other two are located incrementally towards the bottom side 317 of the front edge 315. The grooves do not have to be linear. In some embodiments, any of the putter heads herein can have circular grooves which are configured as a target pattern on the striking face. For example, FIG. 13A illustrates a face view of an alternative configuration of the putter head of FIG. 13 having circular grooves 320′ configured as a target on the front edge 315. The rest of the putter head 310′ is identical to the putter head 310 of FIG. 13.

The distal end 311B of the shaft 311 can be attached to the putter head 310 exactly centered between the toe end 313 and the heel end 314 of the putter head 310. In other embodiments, the distal end 311A of the shaft 311 can be attached to the putter head 310 just short of center between the toe end 313 and the heel end 314 of the putter head 310 to line up the ball off the end of the shaft. In further embodiments, the distal end 311B of the shaft 311 can be attached to the putter head 310 near the heel end 314 of the putter head 310. In further still embodiments, the distal end 311B of the shaft 311 can be attached to the putter head 310 anywhere along the length between the toe end 313 and the heel end 314 of the putter head 310. The insertion of the shaft can be at a variety of positions: front, middle, heel, toe, etc. The shaft can be straight or bent to accommodate insertion site and alignment.

The putter head 310 can be constructed of any suitable material including, but not limited to, metals such as aluminum, brass, and steel. The putter head can be constructed of other materials, including any other natural or synthetic material. Also encompassed by the present invention are golf putters having various markings for alignment of the putter head 310 to a golf ball. Various weights 318A, 318B can be used to adjust the center of mass along an axis running front to back, toe to heel, and/or top to bottom for proper balancing of the putter head 310.

Preferably, the vertical radius of the face of the present invention is less than that of a regulation golf ball, however any radius is encompassed by the present invention. Some preferred embodiments of the putter head 310 have a radius less than half of the radius of a regulation golf ball down to a 0.135 inch (3.43 mm) radius. The regulation golf ball must have a diameter of not less than 1.680 inches (42.67 mm) according to Appendix III of the USGA Rules of Golf. Golf putter head 310 having a narrow radius result in a contact area between the elongate blade and the golf ball which is linear, of narrow width, and essentially horizontal. Such putter head 310 provide reproduce putting distance according to the length of the backswing and putt the golf ball with a minimal skid distance.

Putter head 310 comprises a top side 312 and opposing bottom side 317, the bottom side 317 being adjacent to the ground when addressing a golf ball. Top side 312 and opposing bottom side 317 are of a “D” shape defined by straight linear front edge 315 and an essentially elliptical portion defined by toe edge 313, back edge 316, and heel edge 314. The distance from heel edge 314 to toe edge 313 (length ρ) is greater than the distance from front edge 315 to back edge 316 (width δ). The length to width dimensions can vary, however the length is greater than the width by U.S.G.A. rules. The distal end 311A of the shaft 311 is attached to the top side 312 of putter head 310. The putter head 310 is attached to the distal end 311A of the shaft 311 near front edge 315 at the center of the length of front edge 315 between toe edge 313 and heel edge 314. The distal end 311A of shaft 311 is attached to the putter head 310 near the heel edge 314 and the front edge 315 of the top side 312 of putter head 310. In further embodiments, the shaft 311 is attached to the top side 312 of the putter head 310 through a single plain neck or socket. The length along the neck or socket axis in these embodiments, following any bends, is approximately 5.0 inches (127 mm) or less. The overall length of the putter from proximal end of the shaft 311 to the top side 312 of putter head 110 is at least approximately 18 inches (457 mm).

The front edge 315 of the putter head 310 is linear from toe end 313 to heel end 314 along a horizontal plane, and is convexly curving from top side 312 to bottom side 317 in the vertical orientation. The front edge 315 of the putter head 310 is used as a face to strike a golf ball, and has a vertical radius of curvature which is less than the radius of curvature of a regulation size golf ball. When the golf putter head 310 is used to strike a golf ball, the contact area upon the golf ball and contact area on the front edge 315 of the putter head 310 are both linear with a narrow width, and are also horizontal in orientation. Additionally, the contact area on the ball usually spans the dimple diameter on the golf ball without entering the dimple concavity, so that direction of roll is not influenced by the dimple concavity. Further embodiments of the putter head 310 of the present invention can include any number of grooves in the front edge 315 of the putter head 310. In some embodiments, the groove runs longitudinally along the center line of front edge 315 from toe end 313 to heel end 314 of the putter head 310.

FIG. 14 shows a heel edge view of putter head 310. The putter head 310 tapers from front edge 315 to back edge 316 of the putter head 310, such that the top side 312 of the putter head 310 angles downward towards the bottom side 317 of the putter head 310. A central depression 319 in the top side 312 is bordered by a toe wall 319A and an opposing heel wall 319B, both of which smoothly indent from the top side 312, and a flat front wall 319C. The central depression 319 can be used to pick up a golf ball. In some embodiments a raised curved projection 319D extends slightly above the central depression 319 from the flat front wall 319C, however this is optional. The curved projection 319D provides a semicircular geometry behind the striking area of the putter head. In other embodiments the central depression 319 extends without projections smoothly into flat front wall 319C.

The putter head 310 includes a circular toe weight 318A and a circular heel weight 318B, both secured within corresponding circular depressions into the bottom side 312 towards the toe end 313 and heel end 314, respectively. Toe weight 318A and heel weight 318B can be independently varied in mass to fit the swing of the individual golfer. This is important when fitting the club to the golfer's individual swing to derive the best possible putt. Toe weight 318A and heel weight 318B can be made of any dense material to balance the club swing. The toe weight 318A and heel weight 318B are thereby physically symmetrical with respect to each other, however they can be of different weights to adjust the center of mass from the centerline. Addition of toe weight 318A and heel weight 318B of different masses allows a user to adjust the center of mass of the complete putter head 310. Therefore, the center of mass of the putter head 310 can be adjusted to fall behind any point for contacting golf ball along front edge 315 which is preferred by the user, that is it allows the putter head 310 to be face balanced. Merits of this embodiment is that it allows for posterior and/or inferior weighting, and adjustable weighting by varying materials used for toe weight 318A and heel weight 318B. The center of mass can be shifted from the centerline along the length of the putter head 310 a distance a, from the front of the face along the width of the putter head 310 a distance γ, and from the bottom side of the putter head 310 a distance ε as shown in FIG. 14. In a preferred embodiment, the toe weight 318A and heel weight 318B each are drilled and counterbored for attachment using cap screws (not shown). In a preferred embodiment of the putter head 310, the total weight is 350 grams with the toe weight 318A and the heel weight 318B and cap screws attached. In this embodiment, the length ρ is 3.387, the width δ is 2.236, the face height θ is 0.824, while the center of mass is located such that α=0.087, γ=1.238, and ε=0.408 without cap screws or shaft 311 attached, for posterior and inferior weighting.

The putter head 310 has a contact area between the front edge 315 and a golf ball which is linear, and of narrow width. The vertical radius of the front edge 315 is less than that of a golf ball, and in some embodiments less than half of the radius of a golf ball. In some embodiments of the putter head 310 the vertical radius is ⅛ inch (3.2 mm) to 7/16 inches (11.1 mm). The contact area on the golf ball when struck by the putter head 310 is horizontal in orientation. The slope of the putter head 310 can be front to back (i.e. cross-section narrowing towards the back) or back to front (i.e. cross-section widening towards the back). Preferably, the weight of the putter head 310 of the present invention is between 250 to 450 grams, however other weighted putter head 310 are encompassed by the present invention. The weight of the putter head 310 is most preferably 350 grams. The putter head 310 can be constructed of any metal including, but not limited to, aluminum, brass, and steel. Alternatively, the putter head 310 can be made of any other natural or synthetic material. Further embodiments of the putter head 310 incorporates various means of providing bottom weighting to the putter head 310 and include embodiments having bottom posterior weighting.

Additionally, the contact area on the ball usually spans the dimple diameter. While not wishing to be held to any one theory, the contact area allows the reduction in the release time of the ball from the front edge 315 and thereby the ball starts rolling in less time. Additionally, the horizontal and linear contact area geometry can create a dominant resultant direction of the ball to one plane, while with conventional putters the contact area is circular, which thereby allows for 360° of directional course tracking of the ball. Putting with a conventional putter or one with a round surface produces a circular area of contact on the putter and ball. Putting with the golf putter head 310 of the present invention creates a contact area on the ball which is horizontal and linear.

Another aspect of the putter is that the shaft 311 is attached to the putter head 310 at or near the area of anticipated contact of the front edge 315 to a golf ball. This is in contrast to the typical putter which has a connection at some distance from the contact site where it is attached to some part of the body of the putter. This customary connection requires the force of impact to travel through the mass of the club head material prior to entering the shaft of the putter, thus reducing the feel of the contact. The intimate connection to the anticipated site of contact produces a faster transmission of force of the impact to the golfers hands. This produces an improved “feel” which is important component of putting proficiency.

The putter head 310 provides a potential for various weights 318A, 318B to meet the individual golfers preferences. Various positions of the head weight can be used to optimize the linear nature of the horizontal contact. The weight of the putter head is transmitted or disbursed to a horizontal narrow striking area by adjusting the center of gravity. Additionally, the putter head will accommodate alignment lines or graphics.

The putter head 310 was machined using a computer numerical control (CNC) mill during manufacturing. The ball striking face of the club is the most important part of the club. Initially the face was machined so that half of the width was machined and then the other half was machined. It was found that this created a thin flat line in the center of the face (i.e. transition line). The machining was then modified so that 75% of the face, usually from the top of the face down, was machined so that the transition line did not occur at a ball striking portion of the face. This resulted in a significant performance improvement in the putter. Another method can be to totally machine the face in one motion to avoid the seam.

FIG. 18 through FIG. 21A illustrate typical contact areas made between putter heads of the present invention and a golf ball. Two putter heads, the putter head 110 as illustrated in FIGS. 8-9 and the putter head 310 illustrated in FIGS. 13-17 of the present invention are used in this Example to illustrate typical contact areas. It is to be understood that the other putter head designs disclosed herein will result in similar contact geometries. To determine the contact geometries, the front edges (116A, 315) of two of the described putter heads (110, 310) were first sprayed with a fine powder 32. The powder 32 adhered to the front edges (116A, 315) of the putter heads (110, 310), but was easily removed by contact. A surface of a golf ball 30 coming into contact with the powder 32 was coated with the powder 32 at the contact area (34A, 34B) with the front edges (116A, 315) of the putter heads (110, 310). The powder 32 coated putter heads (110, 310) were then used to strike a golf ball 30. The golf ball 30 was then examined to see the contact area (34A, 34B) left upon the ball 30. This contact area (34A, 34B) represented the area of the ball 30 which strikes the front blade 16A of the putter heads (110, 310). The contact area (34A, 34B) had notable differences to the contact areas of a traditional putter (not shown). The contact area (34A, 34B) of the putter heads (110, 310) are linear with a narrow width, and are also horizontal in orientation.

FIG. 18 illustrates a golf ball 30 showing a typical contact area 34A resulting from striking the ball 30 with a grooved thin-blade putter head (110) of the present invention. FIG. 18A illustrates a closer view of the designated region in FIG. 18. FIG. 19 illustrates a front view of a putter head (110) showing the typical contact area 34A resulting from contact with the golf ball 30 of FIG. 18. FIG. 19A illustrates a closer view of the designated region in FIG. 19. Illustrated in FIG. 20 is a typical contact area (34B) resulting from striking a golf ball 30 with a grooved round face putter head (310) of the present invention. FIG. 20A illustrates a closer view of the designated region on the golf ball 30 in FIG. 20. FIG. 21 illustrates a front view of the putter head (310) showing the contact area (34B) on the front edge 315 resulting from striking the golf ball (30) of FIG. 20. FIG. 21A illustrates a closer view of the designated region in FIG. 21.

The contact area (34A, 34B) upon the golf ball 30 is identified by striking the ball 30 with the putter heads (110, 310) covered with powder 32. The contact area (34A, 34B) is estimated by the powder 32 transferred from front edge 16A of blade 16 onto the golf ball 30 after the ball 30 has been struck with a powder coated front edge 16A of blade 16. The corresponding contact area (34A, 34B) upon the putter head after contacting the golf ball 30 can also be seen where the powder 32 has been removed from the front edge 16A of blade 16. As can be seen both putter heads (110, 310) result in a contact area (34A, 34B) having one or two very narrow horizontal portions. The grooves minimize the contact area, and no more than two ridges contact the ball.

An alternative embodiment of the putter head 310, described previously and illustrated in FIG. 13 through FIG. 17, is illustrated in FIG. 22 through FIG. 23B. This putter head 310 is the same as described previously, except that the face 315 has four projections of various geometries (330, 330′ or 330″). FIG. 22 illustrates a face view and FIG. 23 illustrates a cross-sectional view of this embodiment of the putter head 310 with projections 330 in the front edge 315. Alternatively, the projections have other shapes and configurations as illustrated in FIG. 23A and FIG. 23B. The projections (330, 330′ or 330″) provide linear elevated ridges for striking the golf ball such that the contact area is linear, of narrow width, and horizontal in orientation. The projections further minimize the contact area over a face without projections, minimize slip of the golf ball against the face when striking, and improve the linear nature of the contact geometry. The projections (330, 330′ or 330″) can be provided as a continuous piece of the front edges (16A, 116A, 315) of any of the putter heads described herein.

The projections of the present invention can all be parallel to one another and be horizontally oriented as illustrated in FIG. 23A. Alternatively they can all be disposed perpendicularly to the tangent of the arc of the face of the putter head, ie. aligned normal to the arc of the face as illustrated in FIG. 23B. They can also be a combination of either of these configurations, with some projections horizontally oriented and others perpendicularly oriented. Any putter head embodiment disclosed herein can be provided with any of these projections instead of grooves.

Another embodiment of the present invention is provided as a cylindrical putter heads 410 and 510 as illustrated in FIG. 24 through FIG. 26 and FIG. 27 through FIG. 29, respectively. These putter heads 410 and 510 are described in commonly owned U.S. Provisional Patent Application Ser. No. 60/586,318 to Johnson hereby incorporated herein by reference in its entirety. The face 439, 539 of the round cylindrical putter heads 410, 510 have a vertical radius which is preferably less than that of a golf ball 60, however the radius is not necessarily so limited. The round cylindrical putter heads 410, 510 are preferably of a ⅛ (3.2 mm)to 7/16 inch (11.1 mm) radius. A shaft 431, 531 can be attached to the round cylindrical putter head 410, 510 anywhere between the toe end 433, 533 and the heel end 434, 534 of the round cylindrical putter head 410, 510. Preferably, the distal end of the shaft can be attached to the round cylindrical putter head 410, 510 just short of center between the toe end 433, 533 and the heel end 434, 534 of the round cylindrical putter head 410, 510 to line up the ball off the end of the shaft. The weight of the putter head 410, 510 is most preferably 350 grams. Preferably, the weight of the putter head 410, 510 is between 250 to 450 grams. The bar stock or pipe can be of any metal including, but not limited to, aluminum, brass, and steel. Alternatively, the putter head 410, 510 can be made of any other natural or synthetic material. Any shape or size of a cut out is also encompassed by the present invention to allow for manipulation of the center of mass and total weight of the round cylindrical putter head 410, 510. Also encompassed by the present invention are golf putters having round cylindrical putter head 410, 510 with various markings for alignment of the cylindrical putter head 410, 510 to a golf ball 60.

One embodiment of the putter head having a round cylindrical head 410 has a toe end 433 and opposing heel end 434 shown in FIG. 24 through FIG. 26 constructed of stainless steel bar stock. No weights are added to the putter head 430. A shaft 431 can be inserted into an opening 432 in the top of head 430 which is illustrated to be approximately equidistant between toe end 433 and heel end 434 of head 430, however the opening 432 can be placed anywhere along the length of the putter head 430. A right-handed face 439 of the putter head comprises four grooves 430A in the cylindrical putter head. Any number of grooves 430A, however can be provided. The grooves 430A minimize the contact area made between the face 439 and a golf ball, and increase the linear geometry of the contact area. Since the face 439 has a vertical curvature, the contact area made with the golf ball is small, however the grooves 430A decrease the contact area with the ball even further as with all embodiments of the putter heads herein. In this embodiment of the cylindrical putter head 410 grooves 430B are also provided on the opposing side as a left-handed face 438 of the putter head 410. Therefore a right-handed player or a left-handed player can use the putter head and still have grooves upon the striking face.

Another embodiment of the cylindrical putter head has a round cylindrical head 510 with a toe end 533 and opposing heel end 434 as shown in FIG. 27 through FIG. 29 is constructed of stainless steel bar stock. The toe end 533 of the stainless steel bar stock has a beveled edge 533A, and the heel end 534 of the head 60 also has a beveled edge 64A. A bottom 535 of the stainless steel bar stock is machined towards the toe end 533 and heel end 534 to create a machined portion 567 as illustrated in FIG. 29. This machined portion 567 provides a slight curvature to the bottom 535 of the putter head 510 as illustrated in FIG. 27. No weights are added to the putter head 510. A shaft 531 can be inserted into opening 532 in the top 536 of the head 510. While the opening 532 is illustrated slightly off-center towards the heel end 534, the opening 532 can be placed at any location along the top 536 of the head 510. A wedge of the bar stock running axially along the top-back from toe end 533 to heel end 534 along the cylindrical bar stock is removed to provide an elongate cavity 538. Any shape or size of cut out is encompassed by the present invention to allow for manipulation of the center of mass and total weight of the round cylindrical head 510. In the elongate cavity 538, centrally located along the length of the putter head 510 is a sighting line 537. The sighting line 537 runs front to back in the cavity 538 to assist a golfer in aligning the putter head 510 to a golf ball when putting. A striking face 539 of the putter head 510 comprises four parallel, horizontally oriented grooves 530A in the cylindrical putter head 510. While the putter head 510 is illustrated having four parallel, horizontally oriented grooves 530A, any number of grooves can be provided. As with any embodiment of the grooved putter heads of the present invention, the grooves 530A can be cut parallel as illustrated in FIG. 29 or cut perpendicular to a tangent to the curvature of the face 539. The grooves 530A minimize the contact area made between the face 539 and a golf ball, and increase the linear geometry of the contact area. Since the face 539 has a vertical curvature, the contact area made with the golf ball is small, however the grooves decrease the contact area with the ball even further.

A further embodiment of the putter head 610 of the present invention is illustrated in FIG. 30 through FIG. 36. In this embodiment, the putter head 610 includes an elongate flat blade 616 with a runner 618 attached to the blade 616 by means of an Allen screw 619. The elongate flat blade 616 is provided as a top plate 620 and a bottom plate 630 secured together with four Allen screws 640 passing through the bottom plate 630 and into the top plate 620 near each corner. Preferably the top plate 620 and bottom plate 630 are constructed of materials having different densities for weighting purposes. The elongate flat blade 616 includes a rounded front edge 616A and an opposed back edge 616B. A toe edge 616C extends from the front edge 616A to the back edge 616B of the blade. On an opposite side of the blade a heel edge 616D extends from the front edge 616A to the back edge 616B of the blade. A thickness of the blade 616 is defined between a top side 616E of the top plate 620, bordered by each of the edges, and an opposed bottom side 616F of the bottom plate 630. The front edge 616A of the blade 616 used as a striking face for contacting a golf ball between the ends defined by toe edge 616C and heel edge 616D, and the parallel top side 616E and bottom side 616F. The front edge 616A of the blade 616 has a single groove 614, running the length of the striking face from toe edge 616C to heel edge 616D. The groove is located centrally along the height of the striking face between the top side 616E and the bottom side 616F of the front edge 616A. In a preferred embodiment of the putter head 610 the dimensions are two (2) inches in width by one-half (½) inch thickness by four and three-quarters (4¾) inches in length. The top plate 620 is ¼ inch thick and constructed of lighter mass. Preferably the top plate 620 is constructed of aluminum. The lower plate 630 is ¼ inch thick and constructed of heavier mass. Preferably the lower plate 630 is constructed of brass.

The elongate flat blades 16, 116, 216, 616 of the blade putter heads 10, 110, 210 described herein are thin horizontal blades with distance from heel edge 16D, 116D, 216D, 616D to toe edge 16C, 116C, 216C, 616C (length) approximately twice the distance from front edge 16A, 116A, 216A, 616A to back edge 16B, 116B, 216B, 616B (width). The dimension ratios can vary, however the length is greater than the width by U.S.G.A. rules.

All of the putter heads of the present invention can be attached to the distal end of any shaft known in the art. The shaft can be of any type known in the art, including a “belly putter” type, which is longer than a traditional putter, and allows for a style of putting where the proximal end of the putter is stabilized on the player's belly. In some embodiments, the shaft can be of a long putter type, which makes it ideal for a pendulum style of golf stroke. Any grip known in the art can be fitted to the shaft. In some embodiments, the shaft is of a traditional short length, at least longer than approximately 18 inches (457 mm).

The golf putter heads can be affixed to a distal end of any shaft on the top side of the putter heads in the openings such that the projection of the shaft onto the vertical plane through the front edge of the blade is 10° or more. In further embodiments, the shaft is attached such that the projection of the shaft upon a vertical plane through the toe edge of the putter head is 20° or less. In some embodiments, the shaft is attached through a single plain neck or socket. The length along the neck or socket axis in these embodiments, following any bends, is approximately 5.0 inches (127 mm) or less. The overall length of a golf putter from proximal end of the shaft to the outer surface 18C, 118C of runner 18, 118 is at least approximately 18 inches (457 mm).

After striking a golf ball with the putter head 10, 110, 210, 610 the contact area on the golf ball and on the face are small, due to the thin striking face and the grooves. The curvature of the striking face further minimizes the contact area. The contact area on the golf ball and on the face are both linear with a narrow width, and are also horizontal in orientation. Additionally, the contact area on the ball usually spans the dimple diameter on the golf ball without entering the dimple concavity, so that direction of roll is not influenced by the dimple concavity. The one or more grooves minimize the contact area made with the golf ball over a smooth faced putter. The contact area allows the reduction in the release time of the ball from the front and thereby the ball starts rolling in less time. Additionally, the horizontal and linear contact area geometry can create a dominant resultant direction of the ball to one plane, while with conventional putters the contact area is circular which thereby allows for 360° of directional course tracking of the ball.

The geometry of the elongate flat blade putter heads 10, 110, 210, 610 allow for various angles of approach and positions of contact. The elongate flat blade 16, 116, 216, 616 can strike the ball along the center of the ball or off-center of the ball. The angle of approach allows control of roll of the ball. Striking the ball in upward or downward angles of approach can result in straight tracking of the ball, especially when compared to conventional putters. The putter heads 10, 110, 210, 610 can strike the ball in upward or downward angles of approach with little bounce. A golf putter having the putter head 10, 110, 210, 610 can work well off the fringe of the green, and can have a smoother roll when a forward press is used. There is a smoother roll with varying manipulation of the club by the golfer.

The putter heads of the present invention can be constructed of any metal including, but not limited to, aluminum, brass, and stainless steel. Alternatively, the putter heads can be made of any other natural or synthetic material. The putter heads of the present invention include embodiments having further bottom posterior weighting. The weight of the putter head is transmitted to a horizontal narrow striking area by adjusting the center of gravity. Merits of the embodiments having variable weighting is that they allow for posterior and/or inferior weighting, and adjustable weighting by varying the materials used and the thickness of the weights 17A, 17B, 117B. The center of mass of the putter head 10, 110 can be shifted from the centerline along the length, width or thickness of the putter head 10, 110 by configuration of the weights 17A, 17B, 117B. In a preferred embodiment, weights 17A, 17B, 117B, 318A, 318B each are drilled and counterbored for attachment using Allen screws 19, 119 as fastening means. In preferred embodiment of the blade putter heads 10, 110, the total weight is about 350 grams with no added weights 17A, 17B, 117B to about 425 grams with all of the weights 17A, 17B, 117B. In preferred embodiments the weights 17A, 17B, 117B can be added to increase the total weight of the putter head 10, 110 in 25 gram increments. In these embodiments, the center of mass can be located such that there is a posterior and inferior weighting.

EXAMPLE 1

The Sandwich #3 putter head 610 as illustrated in FIG. 30 through FIG. 36 was tested. The first independent test was on the rolled (rounded) face without a groove. The second was with a single groove as illustrated in the Figures. The Sandwich has two layers provided as top plate 620 and bottom plate 630. The bottom plate 630 of this putter head is brass, a heavier metal, and the top plate 620 of the putter head is aluminum, a lighter metal. TABLE 1 Testing data for the Sandwich #3 Putter Head 610. face and groove Putting Efficiency configuration Skid (inches) Index rounded with only a 14 0.86 seam: rounded single 14 0.87 groove rounded three (3) 19 0.78 grooves

The first test showed surprisingly wide sweet spot which extends to ½ inch heel and toe from the center of the face. Contact at the center of face resulted in a Putter Efficiency Index of 0.857, the toe (contact near toe edge) resulted in a Putter Efficiency Index of 0.895 and the heel (contact near heel edge) resulted in a Putter Efficiency Index of 0.8925. The skid resulting from contact at the center of the face was 14.03 inches. All of these results are very good numbers according to this test. When the face has a single groove, the PEI was 0.885 and the skid was 14.1 inches. To summarize, the putter head with no groove or a single groove is best.

It can be just as good or better for the ten foot putt tested on artificial surface with speed of 10.5 on a STIMPMETER® apparatus (USGA, Delaware). The real advantage of the putter head is seen on the golf course with “clinical” testing with harder hits and longer putts. The performance of the putter head is enhanced.

While the present invention is described herein with reference to illustrated embodiments, it should be understood that the invention is not limited hereto. Those having ordinary skill in the art and access to the teachings herein will recognize additional modifications and embodiments within the scope thereof. Therefore, the present invention is limited only by the Claims attached herein. 

1. In a golf putter head with a curved front edge used for striking a golf ball in an essentially linear contact area horizontal to the ground when putting and an opposed back edge, a length defined between a toe edge which extends from the curved front edge to the back edge of the blade and an opposed heel edge, and a thickness defined between a top side bordered by the edges and an opposed bottom side, the improvement which comprises one or more grooves on the curved front edge at least adjacent to a ball contact portion of the head defined by two or more ridges between the grooves, wherein the front edge is curved vertically such that the front edge strikes the golf ball on a small contact area upon no more than two of the ridges.
 2. The putter head of claim 1 wherein the front edge is curved vertically with a radius of curvature less than a radius of the golf ball.
 3. The putter head of claim 1 wherein the front edge has three grooves.
 4. The putter head of claim 1 wherein the one or more grooves are parallel and extend along the length of the front edge from toe edge to heel edge, so as to be horizontal to the ground when putting.
 5. The putter head of claim 1 wherein the front edge used for striking a golf ball is provided as an interchangeable face.
 6. The putter head of claim 1 wherein the one or more grooves have a width of no more than 0.06 inches, a depth of no more than 0.04 inches, and a width to spacing ratio of at least 1:1.
 7. The putter head of claim 1 wherein the one or more grooves have a width of 0.06 inches, a depth of 0.04 inches and are separated by 0.07 inches.
 8. The putter head of claim 1 wherein the putter face has a radius of 0.5 to 0.75 inches.
 9. The putter head of claim 8, wherein the grooves have a 0.06 inch width with a 0.06 inch space between the grooves, a depth which does not exceed 0.04 inches, and wherein the ridges are without sharp edges.
 10. The putter head of claim 1 wherein the thickness of the front edge of the putter head is less than about 0.25 inch (6.4 mm).
 11. The putter head of claim 1 wherein the thickness of the putter head varies from the front edge to the back edge.
 12. In a golf putter head with a front edge used for striking a golf ball in an essentially linear contact area horizontal to the ground when putting and an opposed back edge, a length defined between a toe edge extending from the front edge to the back edge of the blade and an opposed heel edge, and a thickness defined between a top side bordered by the edges and an opposed bottom side, the improvement which comprises one or more projections on the curved front edge at least adjacent to a ball contact portion of the head, wherein the front edge is curved vertically such that the front edge strikes the golf ball on a small contact area upon no more than two of the projections.
 13. The putter head of claim 12 wherein the curved front edge is curved vertically with a radius of curvature less than a radius of the golf ball.
 14. The putter head of claim 12 wherein the curved front edge has three projections.
 15. The putter head of claim 12 wherein the one or more projections are parallel and extend along the length of the front edge from toe edge to heel edge, so as to be horizontal to the ground when putting.
 16. The putter head of claim 12 wherein the curved front edge used for striking a golf ball is provided as an interchangeable face.
 17. The putter head of claim 12 wherein the one or more projections have a width of 0.06 inches and are separated by 0.07 inches.
 18. The putter head of claim 12 wherein the putter face has a radius of 0.5 to 0.75 inches.
 19. The putter head of claim 18, wherein the projections have a 0.06 inch width and have a 0.06 inch space between the ridges.
 20. The putter head of claim 12 wherein the thickness of the front edge of the putter head is less than about 0.25 inch (6.4 mm).
 21. The putter head of claim 12 wherein the thickness of the putter head varies from the front edge to the back edge.
 22. The putter head of claim 12 wherein the projections are parallel to one another and are horizontally oriented.
 23. The putter head of claim 12 wherein the projections are disposed perpendicularly to a tangent of the face of the putter head.
 24. A golf putter having a shaft with a grip at a proximal end and a head at a distal end of the shaft for contacting a golf ball on the ground during putting of the golf ball, the improvement in the head which comprises: an elongate flat blade having opposed ends, with a top side and a bottom side, and a first linear edge extending therebetween, wherein the top side of the blade is mounted on the distal end of the shaft and the first linear edge acts as a striking face for the golf ball and strikes the golf ball in an essentially linear contact area horizontal to the ground, wherein the striking face is curved vertically with one or more grooves at least adjacent to a ball contact portion of the striking face.
 25. A golf putter having a shaft with a grip at a proximal end and a head at a distal end of the shaft for contacting a golf ball on the ground during putting of the golf ball, the improvement in the head which comprises: (a) an elongate flat blade having opposed ends, with a top side and a bottom side, and a first linear edge extending therebetween, wherein the top side of the blade is mounted on the distal end of the shaft and the first linear edge acts as a striking face for the golf ball and strikes the golf ball in an essentially linear contact area horizontal to the ground, wherein the striking face is curved vertically with one or more grooves at least adjacent to a ball contact portion of the striking face; and (b) a runner provided on the bottom side of the blade wherein during putting, the runner acts to space the bottom side of the blade from the ground. 